Opening and shutting apparatus for flow control

ABSTRACT

An opening and shutting apparatus for a flow control to adjust a fluid flow inside a duct, especially, in which a kinematical structure is used, and so the sum of the moment acting on the knob on closing-up the inside of the duct is forced to come to zero, so that the inside of the duct can be stably closed up without special locking projection or spring, etc.

RELATED APPLICATIONS

The present disclosure relates to subject matter contained in priorityKorean Application No. 10-2004-0042083, filed on Jun. 09, 2004, which isherein expressly incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an opening and shutting apparatus for aflow control to regulate the fluid flow inside a duct, more specially toan opening and shutting apparatus for a flow control to regulate thefluid flow inside a duct, in which the sum of the moment acting on theknob comes to almost zero by applying the direction of the appliedpressure force to be toward the rotary center of the knob, while thepressure applied to a damper door by fluid is transferred to a knobthrough a link when the duct inside is closed up.

2. Description of the Related Art

In general, an opening and shutting apparatus for a flow control is akind of device, in which a knob is rotated and the rotary power of theknob is transferred to a damper door arranged inside duct through alink, so that the damper door can go round, and thereby opening andshutting a flow path.

If the damper door is shut by the rotation of the knob, the pressureforce by the fluid is applied to the damper door. In order to withstandthe pressure and to maintain the closed state, a locking notch or aspring, as shown in FIG. 1, had to be specially arranged according toKorean utility model No. 1998-038245.

If the locking notch or the spring is installed in the opening andshutting apparatus for a flow control, it has following problem that aworking process comes to complicated, and disadvantageous that a smoothoperation is impossible because the locking notch, etc. has an effect onthe operating power of the knob, the cost is increased by the partnumber, and a quality problem is caused.

SUMMARY OF THE INVENTION

To solve the above-indicated problems, it is, therefore, an object ofthe present invention to improve the opening and shutting apparatus fora flow control, so that the pressure of fluid can be withstood with aidof kinematical structure without locking notch or spring only when theinside of the duct is closed up, and the closed state therein bemaintained.

Besides, in another aspect of the object, it is to provide a slidinggroove of a bent structure, so that opening and shutting of the duct canbe adjusted just by the knob rotation of a small angle.

To achieve the above object, there is provided an opening and shuttingapparatus for a flow control which includes of a damper door opening andshutting the path inside the duct; a link, connected with the end of thedamper door, in which a sliding groove is shaped; and a knob having acoupling projection to be connected with the sliding groove of the link;wherein a normal line of the points farthest from the rotary center ofthe knob among the contact points between the sliding groove and thecoupling projection of the knob passes the rotary center of the knobwhen the duct inside is closed up, and more preferably that the slidinggroove of the link has a bent shape.

BRIEF DESCRIPTION OF THE DRAWINGS

The above aspects and features of the present invention will be moreapparent by describing certain embodiments of the present invention withreference to the accompanying drawings, in which:

FIG. 1 illustrates an opening and shutting apparatus for a flow controlusing a conventional locking projection in a schematic view;

FIG. 2 illustrates a first embodiment of the opening and shuttlingapparatus for a flow control according to the present invention in aschematic view; and

FIG. 3 illustrates a second embodiment of the opening and shuttingapparatus for a flow control according to the present invention in aschematic view.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An opening and shutting apparatus for a flow control according to thepresent invention includes a damper door 200 for opening and shuttingthe flow path inside a duct; a knob 300 for, formed into the duct,adjusting the damper door 200 with a rotary power, and having a couplingprojection 301 thereon; and a link 400 for, being connected with thedamper door 200, transferring the rotary power of the knob 300 to thedamper door 200 from the point of view that the coupling projection 301of the knob 301 is inserted into the sliding grooves 401 and 402 formedinside the link 300.

The damper door 200 opens and shuts the inside of the duct by beingaxis-supported at the center of the inside of the duct, and, to increasethe closing effect and decrease the noise, pads 201 are formed along thecircumference of the door damper 200.

The link 400 is fixed into the one side end of the damper door 200, andthe damper door 200 and the link have a same rotary center. The slidinggrooves 401 and 402 of the link 400, as shown FIG. 2, can have astraight form, and as shown FIG. 3, or a bent form.

Accordingly, because the rotation speed of the link caused by that ofthe knob 300 depends on the bent angle and form of the sliding groove ofthe link 400, the section requiring a fast rotation of the damper door200 and the section requiring a slow rotation thereof can be adjusted bythe shape of the sliding groove.

The knob 300 transfers the power applied from the outside to the damperdoor 200 through the link 400, so that the opening and the shutting ofthe duct inside can be adjusted. A coupling projection 301 is arrangedon the knob 300, inserted into the sliding grooves 401 and 402 formed inthe link 400, and transfer the rotation power of the knob 300 to thelink 400.

In view of the process in which the duct inside is closed up, a userrotates the knob 300, and then the coupling projection 301 arranged onthe knob 301 slides in the sliding grooves 401 and 402 of the link 400by the rotating knob 300 and rotates the link 400. Accordingly, therotating link 400 makes the door damper 200, which has a same rotaryaxis and whose end is coupled with the link, rotated around the axis.

If the duct inside, as shown FIG. 2 or 3, is closed up by the rotationof the damper door 200, the pressure of fluid is applied to the damperdoor 200. At this time, the power applied to the damper door 200 istransferred to the knob 300 by the link 400. At this moment, thecoupling projection 301 of the knob 300 is located in the end of thesliding grooves 401 and 402 of the link 400, and then the round couplingprojection 301 is surface-contacted with the end of the half-roundedsliding grooves 401 and 402. Because of the surface contact, numberlessmany points exist, but the points located in the farthest from therotary center of the knob among such contact points builds up one line,and the normal line of those indicates the direction of the power whichis applied to the knob by the link. In this case, the direction in whichthe rotary power of the link has an effect on the knob, that is, thedirection 302 of the normal line makes for the rotary center 303 of theknob.

If this structure is provided, the power to make the knob 300 rotated isnot applied to the knob. Namely, the sum of the moment applied to theknob comes to zero. Because there exists no rotary power, the pressureof fluid can be withstood and the closed state be maintained without aspecial coupling notch 1 or spring.

The effects of the present intention can be summarized as follows:

Firstly, when the pressure of fluid acting on the door damper istransferred to a coupling projection of knob, the sum of the momentapplied to the knob comes to zero by means of the kinematical structureonly, without special coupling projection or spring, so that thepressure of fluid can be naturally withstood and the closed state bemaintained.

Secondly, the sliding groove of the link has a bent form, so that therotating speed of the link can be changed, and accordingly, the openingand shutting speed of the damper door be adjusted. That is, the sectionwanting the fast rotation of the damper door and the section wanting theslow rotation thereof can be adjusted according to the bent angle of thesliding groove.

The foregoing embodiment and advantages are merely exemplary and are notto be construed as limiting the present invention. The present teachingcan be readily applied to other types of apparatuses. Also, thedescription of the embodiments of the present invention is intended tobe illustrative, and not to limit the scope of the claims, and manyalternatives, modifications, and variations will be apparent to thoseskilled in the art.

1. An opening and shutting apparatus for a flow control, comprising: adamper door opening and shutting a path inside a duct; a link configuredto be connected with an end of the damper door and in having a slidinggroove formed therein; and a knob having a coupling projection thereonconfigured to be connected with the sliding groove of the link, whereina line normal to a point farthest from a rotational center of the knobamong contact points between the sliding groove and the couplingprojection of the knob passes through the rotational center of the knobwhen the duct inside is closed up.
 2. The opening and shutting apparatusaccording to claim 1, wherein the sliding groove of the link has a bentshape.